Huge difference in transmissions.....the OP has a 700r4 that has a 0.70 overdrive so the cruising RPM would be 30% lower than your truck. From my experience you need 4.10 minimum to make OD useful on the highway with 35" tires. If a person is really interested in stop light racing than slap in something really low like 5.13's. It would actually be pretty tolerable on the highway with the OD as it would be equivalent to 3.60 gears in a non-OD equipped truck. But as mentioned I'm not quite sure how a rear 10-bolt would survive if ran hard like that.
CK5
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gear ratio advice
- Thread starter 89k5350
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Huge difference in transmissions.....the OP has a 700r4 that has a 0.70 overdrive so the cruising RPM would be 30% lower than your truck. From my experience you need 4.10 minimum to make OD useful on the highway with 35" tires. If a person is really interested in stop light racing than slap in something really low like 5.13's. It would actually be pretty tolerable on the highway with the OD as it would be equivalent to 3.60 gears in a non-OD equipped truck. But as mentioned I'm not quite sure how a rear 10-bolt would survive if ran hard like that.
89k5350
1/2 ton status
ok ive been driving my truck around and im telling you its got good acceleration so rebelgregory what do you have 4.10s 35s and 700r4 in?a k5 or k10? im going crazy because my truck has guts but when i tell my self 3.08s and 35s my balls try shooting up in my stomach lol also would i shift kit give a 700r4 more torqe? cause ive got a shift kit in mine
with 3.08s, but it is 
I was in a pinch and didn't have time to look for 3/4 ton axles with 4.10 in them so I had my 10 bolts regeared to 4.10. I don't do any hard wheeling, it's mostly highway driving with the occasional dirt road or ranch thrown in on occasion.
The 4.10's with my 350/700r4 and 33x10.5 BFG's is great on the highway. It stays in OD and doesn't hunt back and forth like my old 3.42's would cause. I don't have a tach so I can't tell you what my RPMs are on the highway, but it's definitely in the 350's comfort zone (not over revving by any means).
If you're going bigger (35"), definitely go with 4.56's or possibly 4.88's.
The 4.10's with my 350/700r4 and 33x10.5 BFG's is great on the highway. It stays in OD and doesn't hunt back and forth like my old 3.42's would cause. I don't have a tach so I can't tell you what my RPMs are on the highway, but it's definitely in the 350's comfort zone (not over revving by any means).
If you're going bigger (35"), definitely go with 4.56's or possibly 4.88's.
89k5350
1/2 ton status
thanks i appreciate it that actually did help ill post up after the gears are changed and let you know what i think of them
I have bought whole 3/4 tons for less than $450. I have a 1/2 ton with 4.10s, a detroit and a truetrac. You are wasting your money if you spend any money on them. I broke my ring gear in my rear one that has a detroit with 33s. If you want 35s you need at least 3/4 ton axles.
89k5350
1/2 ton status
well im getting a different opinion or story from every one and around here the only 3/4 axles around are ones that have been sitting and are asking too much
They're too expensive because you want/need them now. I find the best deals are found on things you had no intention of upgrading, or better yet, something you just paid a lot of money for and are done with now.
I think you'll find that the popular consensus is to find 3/4 ton axles that already have the ratios you need.
I definintely overpaid to get 4.10's. I should've been looking for 3/4 axles right when I bought the truck and learned that it was a much better (and less expensive) upgrade versus re-gearing my factory 1/2 ton axles.
Honestly I don't even look at 1/2 tons anymore unless it is for the body. The only vehicle with 6 bolt wheels I look at are blazers. They are just too weak for anything I want to do. Hell I am DDing a K30.
when i had my old k-10, it had 3.08 gears, I really wanted at least 4.10 gears. I grabbed a 3/4 ton front 10 bolt axle w/ 4.10 gears from a 3/4 ton suburban and stripped the 8 lug outers down and bolted it in the front and put my 6 lug brakes back on, I didn't even have to bleed the brakes. Then for the rear, I hit up craigslist, found a 12 bolt 5 lug 2wd axle with 4.10's for 75 bux because there was a scar in the bearing surface of one of the 5 lug axles. I swapped that in the rear and installed my 6 lug axles from the axle I pulled out and bolted the existing backing plates (that were hanging under the rear of the truck with coat hangers) so I didn't have to bleed those brakes either. It was cheap and easy gear upgrade and my existing rims and tires bolted back on.
Listen to the guys who are telling you to get different axles.
350 with TPI, SM465, 3.42's and 33's, and I split the housing on my 10 bolt going around a corner. Destroyed the driveshaft as well, so even more expense.
An *open* ten bolt will likely hold up to a fair amount of abuse. But since you are talking a locker, you are just throwing money down the drain.
One option not mentioned yet is a later 6 lug 14SF. As long as you don't mind mis-matched front and rear lug studs/nuts, you can use 1/2" in the rear, or stick with the 14MM. If you really wanted to, you can convert the front and rear to 1/2" lugs/studs, and still only need to change the rear axle and front gears.
350 with TPI, SM465, 3.42's and 33's, and I split the housing on my 10 bolt going around a corner. Destroyed the driveshaft as well, so even more expense.
An *open* ten bolt will likely hold up to a fair amount of abuse. But since you are talking a locker, you are just throwing money down the drain.
One option not mentioned yet is a later 6 lug 14SF. As long as you don't mind mis-matched front and rear lug studs/nuts, you can use 1/2" in the rear, or stick with the 14MM. If you really wanted to, you can convert the front and rear to 1/2" lugs/studs, and still only need to change the rear axle and front gears.
89k5350
1/2 ton status
i have 445 dollars to the dollar tht i can spend on the truck and that money isnt increasing and ive looked there arent any axles near me and have you ever bought used axles that have been sitting and needed nothing and were complete and bolted up with no problems or extra money needed? very doubtful
the cheapest option is to leave it alone...
445 yes in the bank.
but NOT going to get the gears AND installed for that.
i layed it all out basicly in a pm to you how much it will cost you to regear the 10 bolts and later resale value .
then told you my price on pair of 1tons with 4.10 gears and rear is from 3/4 ton truck no swap work needed.
yes will need some work as in seals / calipers remaned / and trick joint in the rear / and ubolts.
we are trying to help you get the best bang for the buck and life of the parts . stop read / listen / save your money and start looking for deals there out there just wait till it comes to you.
good luck
but NOT going to get the gears AND installed for that.
i layed it all out basicly in a pm to you how much it will cost you to regear the 10 bolts and later resale value .
then told you my price on pair of 1tons with 4.10 gears and rear is from 3/4 ton truck no swap work needed.
yes will need some work as in seals / calipers remaned / and trick joint in the rear / and ubolts.
we are trying to help you get the best bang for the buck and life of the parts . stop read / listen / save your money and start looking for deals there out there just wait till it comes to you.
good luck
Come on now. Is your truck broken? Do you have ANY reason other than personal gratification to HAVE to spend exactly $445 on parts right now?
Let's see...my first set of axles cost me $225, and other than the fact the truck was built from the ground up, they didn't nickle and dime me. New gear oil, and that was it. Up until I shattered it.
The 14SF cost me less than $300, and I'm comfortable saying that even with it being a gov-lock, I won't destroy it no matter how hard I can possibly be on it. Nickle and dimes here? New brake lines, new wheel cylinders, gear oil. I eventually converted the front and rear to 1/2" lug because that's all you can easily do, and it's by no means a requirement. Big additional expense was driveshaft (mine was already broken, no additional expense to me).
It's your truck, you could paint smurfs all over it for all I care. People that have been there have offered advice, up to you whether you take it or not.
89k5350
1/2 ton status
well right now i know what i got and i know how to wheel smart and im not just going to stupidly hammer on her out on the road but i was just looking to change the gears so the tranny isnt under so much stress and to do a quick drag race ocasionally and unfortunetly we dont have deals on axles like that around here people are asking tripple that for axles not as good
454Sub
5/8 ton status
i found a pair of 10blt/14bt FF with 4.10s and a gov loc (yes pos but works) for 500 a few years back... I would highly recommend waiting a few weeks or awhile before just throwing money into that rear axle, and certainly wouldnt toss an expensive Detroit in it. Them 3/4 tons will bolt right up, you can even reuse the ubolts even though some recommend against it, all you would maybe need is a jump joint in the rear driveshaft, or better yet just pick one up while your saving money and why not spend the extra bit on stainless brakelines as well. In the end, the 3/4ton rear end is a much better addition to the truck. I have 5.13s and 39.5s, and i turn 2800 at 60ish with a 454, gas mileage = crap but it does get up and move around.
let me call a guy tomarow . he had a set of 3/4 tons with 15x10 8 lug rims. 14ff and 4.10 gears
thay were CLEAN take outs from a truck i saw and was a daily driver till the new owner just took the 6" lift out and also swaped to 1/2 ton's few weeks ag. truck was CLEAN solid truck .(old guy wanted stock truck )
might have a deal for ya. if you got cash in hand. i DO NOT have cash to hold on these . you want you got to come threw. if you want them pm me again if you wana deal.
thay were CLEAN take outs from a truck i saw and was a daily driver till the new owner just took the 6" lift out and also swaped to 1/2 ton's few weeks ag. truck was CLEAN solid truck .(old guy wanted stock truck )
might have a deal for ya. if you got cash in hand. i DO NOT have cash to hold on these . you want you got to come threw. if you want them pm me again if you wana deal.
